NHibernate使用入门(五)

CriteriaQuery和HQLQuery知识点

项目结构如图:

Model类库如下

Customer.cs类和Customer.hbm.xml实体映射文件

[Serializable]
public class Customer
    {
public int Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }

public Address Address { get; set; }

public byte[] DbVersion { get; set; }
public int Version { get; set; }
public DateTime Timestamp { get; set; }

public IList<Order> Orders { get; set; }

public Customer()
        {
            Orders = new List<Order>();
        }
    }

---

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" default-lazy="false"
assembly="Ntest"
namespace="Ntest.Entities" 
 >
<class name="Customer">
<id type="int" name="Id">
<column name="Id" />
<generator class="identity"></generator>
</id>
<property name="FirstName"/>
<property name="LastName"/>

<bag name="Orders" cascade="all" lazy="true">
<key column="customerId"
not-null="true"/>
<one-to-many class="Order"/>
</bag>

</class>
</hibernate-mapping>

Order.cs类和Order.hbm.xml实体映射文件

[Serializable]
public class Order
    {
public int Id { get; set; }
public decimal Value { get; set; }
public IList<Category> Categories { get; set; }

public Customer Customer { get; set; }

public Order()
        {
            Categories = new List<Category>();
        }
    }

---

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" default-lazy="false"
assembly="Ntest"
namespace="Ntest.Entities"
 >
<class name="Order" table="Orders">
<id type="int" name="Id">
<column name="Id" />
<generator class="identity"></generator>
</id>
<property name="Value"/>

<many-to-one name="Customer" column="customerId" not-null="true"/>

</class>
</hibernate-mapping>

hibernate.cfg.xml全局映射文件

<?xml version="1.0" encoding="utf-8"?>
<hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
<session-factory>
<property name="connection.driver_class">NHibernate.Driver.SqlClientDriver</property>
<property name="connection.connection_string">Data Source=.\SQLINSTANCE;Initial Catalog=NHibernateDeepDive;Persist Security Info=True;User ID=sa;Password=123456</property>
<property name="dialect">NHibernate.Dialect.MsSql2008Dialect</property>

<property name="query.substitutions">true=1;false=0</property>
<!--<property name="show_sql">true</property>-->
<property name='proxyfactory.factory_class'>NHibernate.ByteCode.Castle.ProxyFactoryFactory, NHibernate.ByteCode.Castle</property>

<!--设定映射文件默认所在的程序集。-->
<mapping assembly='Ntest' />
</session-factory>
</hibernate-configuration>

CriteriaQuery.cs查询类

 public class CriteriaQuery 
    {
        ISessionFactory sessionFactory = new Configuration().Configure().BuildSessionFactory();


        public void SimpleQueries()
        {
            using (ISession session = sessionFactory.OpenSession())
            {
                var result = (int) session.CreateCriteria(typeof (Customer)).SetProjection(Projections.RowCount()).UniqueResult();

                session.CreateCriteria(typeof (Customer))
.CreateCriteria("Orders", "o")
.Add(Restrictions.Gt("o.Value", 90m))
.List<Customer>();

                session.CreateCriteria<Customer>()
.CreateCriteria("Orders", "o")
.SetProjection(Projections.RowCount())
.SetProjection(Projections.GroupProperty("LastName"))
.SetProjection(Projections.Max("o.Value"))
.List();

                foreach (Customer customer in session.CreateCriteria<Customer>().List<Customer>())
                {
                    int orderCound = customer.Orders.Count;
                }

                Console.WriteLine("SimpleQueries_CustomerCount:" + result);
            }
        }

        // NHibernate3新出了新的查询API QueryOver。本节将为您介绍这查询API QueryOver的相关内容。
        //QueryOver构建在NHibernate原有的ICriteria API之上，支持Lambda表达式与扩展方法。
        public void QueryOver()
        {
            using (ISession session = sessionFactory.OpenSession())
            {
                int result = session.QueryOver<Customer>().RowCount();

                IList<Customer> customers =
                    session.QueryOver<Customer>().JoinQueryOver<Order>(cust => cust.Orders).Where(
                        o => o.Value > 90).List<Customer>();

                IList<object> results =
                    session.QueryOver<Customer>()
.SelectList(list =>
                            list.SelectGroup(c => c.LastName))
.JoinQueryOver<Order>(cust => cust.Orders).List<object>();
                Console.WriteLine("QueryOver_CustomerCount:"+result);
            }
        }

    }

HQLQuery.cs查询类

  public class HQLQuery
    {
        ISessionFactory sessionFactory = new Configuration().Configure().BuildSessionFactory();

        public void SimpleQueries()
        {
            using (ISession session = sessionFactory.OpenSession())
            {
                long result = (long) session.CreateQuery("select count(*) from Customer").UniqueResult();
 IList<Customer> customers =
 session.CreateQuery("select cust from Customer as cust inner join cust.Orders as order where order.Value > 90").List
 <Customer>();

 IList results = session.CreateQuery(
 "select cust.LastName, max(o.Value) from Customer as cust inner join cust.Orders as o group by cust.LastName").List();

 Console.WriteLine("HQLQuery_SimpleQueries:" + result);
 }

 }
 }

主程序

class Program
 {
static void Main(string[] args)
        {
//CriteriaQuery query = new CriteriaQuery();
//query.SimpleQueries();
//query.QueryOver();
//---------------------------------------------------
            HQLQuery hq=new HQLQuery();
            hq.SimpleQueries();
            Console.ReadKey();
        }
    }

运行结果